The Russian invasion of Ukraine in February 2022 and Ukraine’s remarkable resistance to Russian aggression have triggered reams of analysis.[1] Perhaps no aspect of the war in Ukraine has sparked more discussion—particularly among American observers and analysts—than the nuclear dimension of the conflict and the extent to which Russian and American nuclear weapons are affecting the calculations of the various actors involved. The “bomb in the background” of the conflict has never been far from the forefront of analysis.[2] This is obviously reasonable, given the possibility that the conflict might escalate in unpredictable ways and the regular Russian nuclear threats (of varying degrees of explicitness). This essay argues, however, that, at least at this point, what is most notable about the role that nuclear weapons appear to be playing in the war in Ukraine is how little new information the war has generated about the role that nuclear weapons play in international politics.
H-Diplo | Robert Jervis International Security Studies Forum
Policy Roundtable III-3
Ukraine and Nuclear Weapons
21 February 2024 |PDF: https://issforum.org/to/jprIII-3 | Website: rjissf.org | Twitter: @HDiplo
Editor: Diane Labrosse | Commissioning Editor: Jennifer L. Erickson | Production Editor: Christopher Ball
Contents
Response by Mark S. Bell, University of Minnesota. 20
“Plus ça change, plus c’est la même chose: The Old Lessons about Nuclear Weapons being Re-Observed in Ukraine”
by Mark S. Bell, University of Minnesota
The Russian invasion of Ukraine in February 2022 and Ukraine’s remarkable resistance to Russian aggression have triggered reams of analysis.[1] Perhaps no aspect of the war in Ukraine has sparked more discussion—particularly among American observers and analysts—than the nuclear dimension of the conflict and the extent to which Russian and American nuclear weapons are affecting the calculations of the various actors involved. The “bomb in the background” of the conflict has never been far from the forefront of analysis.[2] This is obviously reasonable, given the possibility that the conflict might escalate in unpredictable ways and the regular Russian nuclear threats (of varying degrees of explicitness). This essay argues, however, that, at least at this point, what is most notable about the role that nuclear weapons appear to be playing in the war in Ukraine is how little new information the war has generated about the role that nuclear weapons play in international politics.
In fact, the key lessons that the war in Ukraine has revealed about nuclear weapons are old lessons that have been revealed many times since 1945: nuclear weapons deter (to a point); they enable (to a point); and those deterrent and enabling effects emerge directly from the catastrophic destruction that nuclear weapons can cause and the risk that events within a crisis could spiral out of control. The war in Ukraine so far should, therefore, not significantly change our assessment of the role that nuclear weapons play in international politics. This fact is itself of importance. Thankfully, the war in Ukraine has to this point reinforced old lessons about nuclear weapons rather than triggering new ones. World leaders should work to keep it this way. Ultimately, the action that would potentially trigger fundamentally new lessons about nuclear weapons is the one that has yet to be taken: Russian use of nuclear weapons.
The Enduring Lessons of Nuclear Weapons
The most basic political effects of nuclear weapons are those that have most influenced the conduct of the war in Ukraine. I focus on three. First, nuclear weapons deter. Second, precisely because nuclear weapons deter, they also enable states to pursue more belligerent behaviors behind the deterrent shield that they offer. Third, these political effects emerge directly from the destructive capabilities of nuclear weapons and cannot be separated from the way in which the risk of escalation shapes incentives and behavior. The risk of nuclear escalation, therefore, cannot simply be ignored or managed away while nuclear weapons continue to deter and enable. Rather, nuclear weapons deter and enable precisely because of the risk of nuclear escalation.
Nuclear Weapons Deter
First, and most obviously, nuclear weapons deter. The most basic technical features of nuclear weapons—that they package enormous destructive capacity within physically small weapons, and that there are huge (and perhaps insurmountable) technical difficulties associated with defending against a nuclear attack with any reliability—make nuclear weapons powerful tools of deterrence because they massively increase the costs and risks associated with conflict with a nuclear-armed power.[3] This is the most basic and well-understood political effect that nuclear weapons have, but it is also the one most that has most clearly shaped the conflict dynamics in the war in Ukraine.
While the conflict is causing devastatingly high casualties and enormous physical and economic damage to Ukraine, both Russia (as a direct belligerent) and the United States (as a patron of Ukraine) are nonetheless constraining their behavior in important ways. Deterrence is not absolute, but both countries are deterred from a range of actions they might otherwise find attractive in the conflict because of the fear that those actions may escalate the conflict in ways that could lead to nuclear use. Russia is deterred from attacking the western arms shipments in NATO countries en route to Ukraine—especially in Poland. Russia may also be deterred from widening the war by directly attacking NATO members or escalating the war in Ukraine by using tactical nuclear weapons. Russia reasonably fears that these actions would dramatically increase the risk of the United States from bringing its full power to bear on the conflict. For its part, the United States is deterred from intervening directly in the conflict, and from supplying Ukraine with some types of military capabilities that it fears might unduly provoke Russian escalation.
Deterrence is therefore working in both directions—but its political effects within the conflict are not necessarily symmetric. As Nina Tannenwald has observed, nuclear deterrence in this case may be working primarily to Russia’s advantage: “Were nuclear weapons not in the calculus, the United States and NATO would be able to employ their superior conventional firepower more effectively in Ukraine’s defense to win the war quickly. But [Russian President Vladimir] Putin’s nukes neutralize the West’s conventional military superiority.”[4] These dynamics are deeply unpleasant and frustrating for American policymakers who are used to being free to deploy the full might of their country’s military capabilities against non-nuclear-armed states in the pursuit of ambitious political goals.[5]
Some analysts have responded to this frustration by boldly declaring that the United States should ignore the deterrent effects of Russian nuclear weapons and act confidently and free of fear of Russian escalation in order to enable a decisive Ukrainian victory. The historian Timothy Snyder has declared that US leaders should be “ashamed of [their] discussion of nuclear war” and that Russian “nuclear talk” is causing “Europeans and North Americans to deter themselves.”[6] Analyst Anne Applebaum argues that “there is no indication…[that Russian nuclear threats] are real,” and that the United States should unapologetically commit itself to a Ukrainian victory.[7] Nuclear disarmament advocate Beatrice Fihn argues that “Ukraine shouldn’t have to choose between its sovereignty and risking nuclear war…that’s why we have to stop being so stupid by continuing to say nuclear deterrence works.”[8] For Keir Giles, “the West’s repeated emphasis of its fear of escalation proves to Russia that threats work, irrespective of how implausible they may be or how often they have been shown to be empty.”[9] According to this line of argument, the West is not simply being deterred, but is rather choosing to be deterred by illusory threats.
This line of argument is misguided. The fundamental problem is not one of “self-deterrence” or a policy choice by western governments to feel deterred. What we are observing is run-of-the-mill, straightforward, basic, plain-vanilla deterrence. That deterrence is triggered not by a lack of fortitude on the part of American policymakers. Rather, it is caused by the existence of thousands of Russian nuclear weapons, any one of which could destroy a major American city and which are under the control of a leader whose state of mind is unreadable, whose power relative to senior military officials and other key actors within the Russian state is ambiguous, whose intentions are unknown, and whose red lines for nuclear use are unclear.[10] The caution this basic reality induces, and which the Biden administration has thus far recognized, is the most basic and long-understood political effect that nuclear weapons have.
Of course, the United States could do what Snyder, Applebaum, Fihn, Giles, and others recommend and ignore the possibility of nuclear use or act as if Russian nuclear use is impossible. As I discuss further below, the United States cannot in fact do that without taking on risks that the conflict could escalate in potentially catastrophic ways. Deterrence exists precisely because Russian nuclear use—whether wholly deliberate or as a result of miscalculations or accidents—is in fact possible.
Nuclear Weapons Enable
Nuclear weapons deter. But precisely because they have powerful deterrent effects, they also have broader effects on the calculations that states make about engaging in other political behaviors. Nuclear weapons, in short, do not simply prevent other states from doing things. They also enable states to do things.
The extent to which nuclear weapons enable certain actions and the types of behaviors, and the circumstances under which different states will take advantage of different enabling effects, have long been debated by scholars.[11] Nonetheless, the basic dynamic is well understood, and is in fact a logical and inevitable consequence of deterrence. If nuclear weapons deter an adversary of a state from taking action x, then the cost-benefit calculations for the state associated with any behavior it might take for which x might be a negative consequence will change. Because the downside risk of x is reduced, that behavior will become more attractive. Nuclear weapons do not give countries free rein to do whatever they want in international politics, but the enabling effects of nuclear weapons are real and meaningful. Whether it is Pakistan using nuclear weapons to pursue revisionist goals in Kashmir, the United Kingdom using nuclear weapons to act more independently of the United States during the Cold War, or the United States using nuclear weapons to underpin an unprecedented and globe-spanning array of alliances in the aftermath of World War Two, nuclear-armed states have well understood the enabling effects of nuclear weapons and have often used nuclear weapons to facilitate a broad range of foreign policy goals.[12]
It is reasonable to think that these dynamics may well have played a role in enabling Putin’s decision to invade Ukraine. To come to this conclusion, one does not need to believe that Putin believes that Russia’s nuclear weapons serve a military purpose in Ukraine or that he might actively want or plan to use them. The basic assumption is that Russian nuclear weapons deter US involvement in Ukraine. Because of that, invading Ukraine (in expectation) becomes a less risky and dangerous proposition for Russia than it would have been without Russian nuclear weapons and the ability they offer to keep the more conventionally powerful United States at arm’s length in the conflict. Nuclear weapons, in this way, act as a shield behind which Russia can engage in aggression, in much the same way that they have for other nuclear-armed states such as Pakistan or South Africa in the past, and in much the same way that some nuclear aspirants such as Saddam Hussein’s Iraq planned to use nuclear weapons if they acquired them.[13] We should therefore be skeptical of claims along the lines that Russian behavior is “set[ting] a highly dangerous precedent as it incentivizes other states to acquire or instrumentalize their own nuclear weapons given their obvious benefits.”[14] Similarly, arguments that other states are drawing profoundly new lessons about the way in which nuclear weapons enable belligerent behaviors by observing the war in Ukraine should be treated with skepticism.[15] While the political benefits that Russia is reaping from its nuclear weapons are meaningful, they flow logically from the deterrent effect that weapons have; have been repeatedly observed in other cases in the past; and should be familiar to any observer of nuclear history (or any state).
Much as with the deterrent effects of nuclear weapons, the enabling effects of nuclear weapons are a two-way street. Just as Russian nuclear weapons are enabling Russian behavior, US and NATO nuclear weapons are also enabling US behavior in the conflict. The United States has provided Ukraine with tens of billions of dollars of security assistance that has been critical to the effectiveness and potency of Ukraine’s military resistance,[16] has openly transported those capabilities through NATO allies to Ukraine’s borders and into Ukraine, and has even been willing to send President Joe Biden to walk around Kyiv with the full confidence that Russia would not to harm him.[17] Indeed, the fact that the United States deliberately alerted Russia to Biden’s Ukraine visit—because to do so increased rather than decreased Biden’s security—is itself a powerful indication of both sides’ awareness of the simultaneously enabling and deterring power of nuclear weapons and the semi-collaborative nature of efforts to avoid escalation.[18] Both the deterrent and enabling effects of nuclear weapons are therefore shaping the dynamics of what both sides can do, and what they are choosing not to do, in this conflict. Both sides are seeking a sweet spot between achieving their political goals in the conflict (at each other’s expense) while avoiding taking actions that will violate each other’s red lines and/or risk triggering unpredictable escalation.
Again, these dynamics are not new. They are persistent features of international politics in the nuclear era. Throughout the Cold War, the United States and Soviet Union competed in ways that reflected the simultaneously enabling and deterring effects of nuclear weapons. Both sides competed vigorously with each other in a range of conflicts, crises, and proxy wars: whether in Korea, Cuba, Germany, Angola, Afghanistan, or elsewhere. But the two sides also limited their behaviors and frequently “tacitly colluded” to reduce escalation pressures and keep conflicts well below the nuclear threshold.[19] Indeed, many Cold War crises appear to have been characterized less by straightforward coercive contests of will than by competitive efforts by the superpowers to outmaneuver each other in order to avoid being the first to have to take unambiguously escalatory actions.[20] This combination of competition and co-operation has been a regular feature of great power competition in the nuclear era. And these familiar dynamics are again playing out today in Ukraine.
The Political Effects of Nuclear Weapons Emerge from Risk
Nuclear weapons thus have significant and simultaneous deterring and enabling effects, and these effects are clear in the Russian war on Ukraine. Those political effects, both those which are working to the benefit of the West and those which are working against it, cannot be separated from technological features of nuclear weapons: the huge destructive capabilities that nuclear weapons offer and the possibility of the conflict escalating to the nuclear level. This connection cannot be sidestepped, managed, or wished away: in the words of Jeffrey Lewis and Aaron Stein, “the irreducible risk that things might go terribly wrong is necessary for nuclear deterrence to function…it is a feature, not a bug.”[21] As Thomas Schelling understood and compellingly articulated nearly sixty years ago, nuclear-armed states can still compete vigorously to achieve political goals at each other’s expense, even when both possess nuclear weapons and when neither can credibly threaten to launch a nuclear war over the subject of their competition.[22] The process of that competition cannot be made risk-free, and the effort to win such contests involves manipulating and, ultimately, subjecting oneself to, the risk of nuclear war.
The history of nuclear crises backs up this way of thinking about nuclear weapons and the way in which they generate political effects. While nuclear crises vary in the risks associated with them, there have also been repeated occasions when accidents, bad luck, or imprudent decisions by individuals (by people at various levels of seniority within governments or militaries) could plausibly have triggered events that could have led to escalation across the nuclear threshold.[23] Assessing precise probabilities that nuclear crises may spiral out of control may be difficult if not impossible, which makes carefully identifying the escalatory risk associated with any given action challenging.[24] Schelling’s analogy of climbers tied together and close to a cliff-face may be decades old at this point but remains powerful: “while either can deliberately jump off, he cannot credibly pretend that he is about to. Any attempt to intimidate or to deter the other climber depends on the threat of slipping or stumbling. With loose ground, gusty winds, and a propensity toward dizziness, there is some danger when a climber approaches the edge.”[25] Because of this, moves towards the edge—which both the United States and Russia have taken—can have coercive effects, simultaneously deterring possible behaviors by the other and enabling their own behaviors.
As a result, it is misleading to nitpick any individual act of nuclear brinkmanship as mere bluster or as being strategically inconsequential. One of the climbers in Schelling’s famous analogy can reasonably tell the other climber that “moving toward the edge doesn’t convince me you’ll jump off,” but that misses the point—and misunderstands the coercive power—of the action. Similarly, consider Putin’s announcement that he planned to deploy tactical nuclear weapons in Belarus.[26] It is perfectly reasonable to be skeptical of the strategic significance of such a move. For example, Fred Kaplan argued that “Putting another dozen or so [nuclear weapons] on Belarusian soil gives Putin no advantage, nor does it alter the strategic situation in any way. It doesn’t put Russian nukes any closer to Ukraine than many already are. Nor would a nuclear weapon launched from Belarus exempt the Russian homeland from nuclear retaliation by the West.”[27] Kaplan is entirely correct in his analysis, but this misses the point: Putin’s threat (and action if he were to go through with it) is not designed to alter the strategic balance or rational calculations that might lead to nuclear use. Rather, it creates some additional unpredictability and risk by creating additional avenues by which things could spiral out of control.
For example, transporting nuclear weapons, storing them in a new location, putting new individuals and security structures in charge of their security, adapting command and control systems for the possible use of nuclear weapons in another country, subjecting their security to the political stability of an additional country, and so on, all modestly increase the number of ways in which accidents, miscalculations, or misjudgments might occur. Similarly, actions that the United States and its allies have taken place similar coercive pressures on Putin. For example, consider the decision to bring Finland into NATO, which doubles the length of the direct border between NATO and Russia and thus adds a range of plausible escalatory pathways to those that already exist between NATO and Russia.[28] As Schelling understood,
many…actions and threats designed to pressure and intimidate would be nothing but noise, if it were reliably known that the situation could not get out of hand. And if they definitely would lead to war, they would not be taken…what makes them significant and usable is that they create a genuine risk…that the thing will blow up for reasons not fully under control.[29]
The risk that things might spiral out of control is not a problem that can be managed out of existence while nuclear weapons continue to have political effects. Rather, it is the mechanism through which nuclear weapons have political effects. And, much like the deterrent and enabling effects of nuclear weapons, it is a well-understood and regularly observed feature of politics under the shadow of nuclear weapons. Again, therefore, the lesson of the war in Ukraine is one that should be well-established and largely familiar.
The Enduring Lessons of Nuclear Weapons
We are now some seventy-five years into the nuclear era. Much about the way in which nuclear weapons affect international politics remains ambiguous. This is largely good news and reflects the limited evidentiary base on which scholars can draw.[30] Nuclear weapons have not been used directly in a conflict since 1945; only ten countries have decided to acquire nuclear weapons (one of whom subsequently gave them up); and the role that nuclear weapons have played in key events remains subject to a range of historical interpretations. But despite that, scholars have settled on some basic conclusions about nuclear weapons. These conclusions are inevitably somewhat tentative given the limited historical evidence they can draw on, but for the most part they appear to be being reinforced by events in Ukraine. Nuclear weapons deter (to a point); they enable (to a point); and those deterrent and enabling effects emerge directly from the catastrophic destruction nuclear weapons can cause and the risk that events could spiral out of control.
That these lessons are familiar ones also means that we have not yet seen in Ukraine the kind of actions that could cause a genuine reassessment of the role that nuclear weapons play in international politics. Ultimately, the action that might trigger genuinely new lessons about nuclear weapons is exactly the one that thus far has successfully been avoided: the Russian use of nuclear weapons. As noted, up until this point, the lessons learned in Ukraine about nuclear weapons have largely reinforced what we already know about nuclear weapons. But Russian use of nuclear weapons would open a new world. The dynamics of such a world are far harder to anticipate. The lessons we might learn about nuclear weapons in such a world may be fundamentally new ones, whether about the effects of nuclear weapons, the power of the nuclear taboo, the coercive value associated with nuclear use, and the dynamics of escalation beyond the nuclear threshold. We should all hope that those are lessons that we will not need to learn, even if avoiding them requires difficult choices and uncomfortable restraint.
Contributors:
Mark S. Bell is an Associate Professor of Political Science at the University of Minnesota. His research examines issues relating to nuclear weapons and proliferation, international relations theory, and US and British foreign policy. His book, Nuclear Reactions: How Nuclear-Armed States Behave, was published by Cornell University Press (2021), and other work has been published in journals including International Organization, International Security, International Studies Quarterly, the Journal of Conflict Resolution, the Journal of Strategic Studies, and Texas National Security Review. He holds a PhD in Political Science from the Massachusetts Institute of Technology, an MA in Public Policy from Harvard Kennedy School and a BA in Politics, Philosophy, and Economics from St. Anne’s College, Oxford University.
Henrik Stålhane Hiim is an Associate Professor at the Norwegian Institute for Defence Studies at the Norwegian Defence University College. His main research interests are nuclear strategy and nonproliferation, as well as Chinese foreign and security policy. His work has appeared in outlets such as International Security, International Affairs, Journal of Contemporary China, Survival, and War on the Rocks. Hiim holds a PhD and an MA in political science from Oslo University.
Amy J. Nelson is a Fellow in the Foreign Policy program and with the Strobe Talbott Center for Security, Strategy, and Technology at the Brookings Institution where her research focuses on emerging, evolving, and disruptive technologies and their impact on proliferation. She is currently writing a book on arms control as uncertainty management.
Polina Sinovets, PhD, is a Founder and a Head of Odesa Center for Nonproliferation (OdCNP), Odesa I.I. Mechnikov National University (Ukraine). In this role, she leads the education, training, research, and outreach activity of OdCNP. She is the author and co-author of multiple publications on nuclear weapons policy of the US and Russia, nuclear deterrence, strategic stability, and European security in the Bulletin of the Atomic Scientists, NATO Defense College Research Papers, War on the Rocks, as well as the editor of Ukraine’s Nuclear History: A Non-Proliferation Prospective (Springer, 2022), Arms Control and Europe. New Challenges and Prospects for Strategic Stability (Springer, 2022), Russia’s War on Ukraine: The Implication for the Global Nuclear Order (Springer, 2023). She is currently affiliated with Odesa I.I. Mechnikov National University, Ukraine; and La Foundation pour la recherche stratégique, France.
“Old Lessons for a New Rivalry”
by Henrik Stålhane Hiim, The Norwegian Institute for Defence Studies
In the wake of Russia’s invasion of Ukraine, concerns over aggression from China against Taiwan have increased. Seeing how nuclear weapons deterred US intervention in the Ukraine war despite Russia’s conventional inferiority, China could take a page out of Russia’s playbook and invade Taiwan while hiding behind a nuclear shield—or so the story goes.[31]
If Chinese leaders are indeed learning from the Ukraine war that nuclear weapons make it “safe” to engage in conventional aggression, it could spell terrible news for peace and stability in East Asia. However, in his thoughtful essay, Mark Bell highlights that we should be skeptical about claims that other states “are drawing profoundly new lessons about the way in which nuclear weapons enable belligerent behaviors.” Bell is not denying that nuclear-enabled belligerency—such as a Chinese attempt to invade Taiwan—could occur. Rather, he argues that policymakers in China and elsewhere were already aware that nuclear weapons can enable certain types of behavior, including aggression.
Bell’s skepticism is well-founded. There are two key reasons to be cautious about the alleged nuclear lessons Chinese leaders might draw from Ukraine. First, there is limited evidence of a rethinking in China about the role that nuclear weapons play in international politics since the outbreak of the Ukraine war. Concerns about nuclear weapons working as a shield and emboldening China in a conventional conflict are certainly valid, but they are not new, and have debated among scholars for more than a decade.[32]
Second, any claims of Chinese leaders learning from the situation in Ukraine overlook another enduring feature of the nuclear age that Bell only hints at in his essay: in conflicts between nuclear powers, the outcomes are influenced not only by the balance of power. They are also strongly influenced by the balance of resolve—the relative willingness to risk nuclear war.[33] In a Taiwan conflict, US resolve would likely be greater than it has been in Ukraine. That is mainly good news, as the threat of US intervention will hopefully deter China. But if deterrence fails, and war breaks out in the Taiwan strait, the risk of nuclear escalation could be even greater than in the Ukraine conflict.
An Old Paradox
As Bell highlights, that nuclear weapons can enable certain behaviors, including aggression, should be “familiar to any observer of nuclear history (or any state).” Chinese leaders are unlikely to be an exception. Indeed, scholars have expressed concerns about Chinese nuclear-enabled aggression against Taiwan for more than a decade. At the heart of these concerns are the claim that Chinese leaders believe quite strongly in the so-called stability-instability paradox, where strategic stability and mutual nuclear deterrence make it seem “safe” to engage in limited conflicts.[34] A consequence of these alleged beliefs is that China, as Avery Goldstein suggested in 2013, may “be more willing to take steps that risk triggering a crisis.”[35]
Prior to the Ukraine war, China’s nuclear expansion already reinforced concerns about the stability-instability paradox and nuclear-enabled aggression against Taiwan. News of China building more than 300 missile silos in three fields broke in 2021, and the US Department of Defense has projected that China will possess 1,000 warheads by 2030, which would constitute a major build-up from the estimated 500 warheads in its current stockpile.[36] As Abraham Denmark and Caitlin Talmadge have highlighted, an enlarged and improved Chinese arsenal “puts the United States and China into a deeper condition of nuclear stalemate” which may make conventional conflicts seem “safer” to fight for Chinese leaders.[37] Another recent study finds evidence that China’s build-up is consistent with what the authors term the “nuclear shield model.”[38]
Nevertheless, it is important to highlight that there are other possible, albeit not mutually exclusive, explanations for China’s nuclear expansion. Notably, Chinese concerns about US threats to China’s nuclear arsenal have increased in recent years, and bolstering the survivability of its forces appears to be a powerful driver of this expansion. Chinese-language sources contain little direct discussion of the need for a nuclear shield.[39] In other words, the hypothesis that a desire for a sturdier shield drives China’s build-up remains plausible but unproven.
Even if the shield hypothesis is correct, there is still limited evidence to suggest that the Ukraine conflict provided Chinese officials or analysts with fundamentally new lessons. The People’s Liberation Army (PLA) will certainly study the conflict closely in order to improve its grasp of modern warfare, and some analyses of the nuclear dimension have started to surface. An article from the PLA Daily from January this year highlighted how Russia demonstrated “resolve and strength to deter NATO from direct military intervention” through nuclear signaling and employment of nuclear-capable missiles such as the Kinzhal.[40] But even if it is interesting that Chinese analysts are drawing such conclusions, this points to dynamics that numerous analysts elsewhere have highlighted. It is unlikely that they represent radically new ideas to Chinese observers.
“The Critical Balance of Resolve”
The Ukraine war demonstrates another enduring lesson of the nuclear age that Bell does not mention explicitly, namely how the balance of resolve, or the relative willingness to risk nuclear escalation, is critical in conflicts.[41] In Ukraine, this balance remains skewed heavily in favor of Russia. For understandable reasons, US leaders have not considered Ukraine important enough to risk nuclear war by intervening directly. Prior to the Ukraine invasion, the United States effectively declared that given the rise of nuclear escalation, it wanted to avoid a military confrontation with Russia. President Joe Biden stated in December 2021 that the stationing of American troops on the ground in Ukraine was “not on the table.”[42]
The situation in the Taiwan Strait is very different, thus dampening the relevance of any lessons Chinese observers might draw from Ukraine. To be sure, US resolve in a Taiwan conflict remains to be seen, and there is extensive debate about whether the United States should maintain its policy of “strategic ambiguity,” where it indicates an interest in defending Taiwan but without providing clear security guarantees.[43] Nevertheless, US resolve would likely be much stronger than it is in Ukraine. The “strategic ambiguity” policy has moved towards clearer promises to Taiwan in recent years. Even if his advisors have later walked back his comments, Biden has stated on four occasions that the United States will intervene if China attacks.[44]
Stronger US resolve over Taiwan has several key implications. At the outset, it bolsters deterrence in the Taiwan Strait. Chinese leaders harbor few illusions. While they may hope that the United States abandons Taiwan, they are planning for a war involving the United States. Drawing red lines and deterring US intervention would be much harder for China than it has been for Russia. In all likelihood, this will induce greater caution among Chinese leaders about starting a war. Put differently, the point to which nuclear weapons would “enable” aggressive behavior, as Bell puts it, is different in the Ukraine war.
At the same time, the strong resolve by both actors highlights why the conventional balance of force matters more in Taiwan than it does in the Ukraine context. If both China and the United States are willing to fight a limited conflict under the nuclear shadow—despite the risk of escalation—conventional deterrence is critical.[45] This is where one of the greatest challenges to the United States and Taiwan lies. Although the US might still prevail in a Taiwan conflict scenario, the conventional balance of force is increasingly tilting in China’s favor. Left unchecked, this will weaken US deterrence.[46]
Stronger mutual resolve further means that the risk of nuclear escalation in a Taiwan conflict could be even greater than in Ukraine. At the outset, a Taiwan conflict would likely entail the dynamics Bell observes, in which “both sides are seeking a sweet spot,” attempting to achieve political goals (or even conventional military goals) without triggering escalation. But in a situation where China and United States are at war, finding this sweet spot could prove difficult. Both parties could prove willing to subject themselves to significant risk.
The likelihood of deliberate escalation by either actor is limited (and China’s case, it would be at odds with its no-first-use pledge). Nevertheless, it cannot be ruled out, and both the United States and China increasingly fear that the other could threaten or even resort to limited first nuclear use to coerce the other to back down in a conflict.[47] Moreover, several studies have warned of the risk of inadvertent nuclear escalation. If the United States strikes targets on the Chinese mainland that are associated with Chinese nuclear forces or sinks a Chinese ballistic missile submarine, China could feel a strong pressure to respond.[48] Importantly, inadvertent escalation would not necessarily only be the result of bad luck, but also of willingness to press an advantage too far, without observing escalatory risks.
A New Great Power Rivalry in an Enduring Nuclear Shadow
Mark Bell’s essay is persuasive in arguing that the Ukraine war provide few fundamentally new lessons about nuclear weapons and international politics. This applies also to Chinese leaders. The idea that nuclear weapons can enable aggression is unlikely to be new to them. Furthermore, they are well aware that Taiwan’s status is different from that of Ukraine, and probably recognize that US resolve will be greater in a conflict over Taiwan.
At the same time, the Ukraine war points to the importance of relearning old lessons about deterrence and nuclear risk. Analysts frequently point to how new technology and a greater number of actors make the current nuclear environment different from that of the Cold War. While they are not wrong, there is a tendency to overlook how many dynamics remain similar. This includes the lessons that Bell highlights about how nuclear weapons deter, enable, and generate risk, as well as other familiar lessons about the importance of the balance of resolve and arms race pressures.
The intensifying rivalry between the United States and China is unfolding under an enduring nuclear shadow. Unfortunately, nuclear weapons and deterrence are gaining greater importance in the relationship. There are ample signs that an action-reaction dynamic is underway, which could lead to an arms race; the possibility of war in the Taiwan strait is far from trivial. All of this reinforces the renewed relevance of old lessons about nuclear weapons.
“The Great Deterrence Rethink: On Nuclear Weapons Use in the Russia-Ukraine War, the Operative Phrase is ‘Not Yet’”
by Amy J. Nelson, The Brookings Institution
Mark Bell’s essay carefully constructs an argument about the unchanging role of nuclear weapons in the security of states. Nuclear weapons continue to deter and enable (both to a point) he argues, because of their potential destructive power. Moreover, the Ukraine war has demonstrated that deterrence “holds” and nothing new has been revealed by the invasion and subsequent war about how deterrence works. The piece comes at a time when many scholars are engaged in a whole scale rethinking deterrence,[49] in light not only of the Ukraine war but also the evolving nature of weapons of war leading in part to conventional weapons systems rivaling nuclear ones in their destructive power, and the expansion of the traditional battlefield to include the gray zone. The implication of this new wave of scholarship is that the careful balance of terror that has undergirded the deterrence (and arms control) architecture since the 1940s can no longer be taken for granted. Bell argues, however, that no evidence from the Ukraine war disrupts these truths: nuclear weapons are working in Ukraine as they have always, deterring and enabling—each to a point. “The war in Ukraine so far should, therefore, not significantly change our assessment of the role that nuclear weapons play in international politics,” he concludes. Ultimately, Bell’s piece is likely to endure as a major contribution to what will likely be “first wave” thinking on the implications of the Ukraine war on deterrence thinking.
Because the idea that deterrence does not work[50], or is not a reliable construct, is indeed unsettling—if not downright frightening—Bell’s argument is likely comforting to many. If nuclear weapons play the same role today as they did during the Cold War, for example, there is a stable pattern of countries not using nuclear weapons. Furthermore, Bell’s piece suggests that such efforts at “rethinking deterrence,” may not be necessary.
And yet, it feels prudent to spend a moment exploring initial high-intensity panic over deterrence that erupted when Russia first invaded Ukraine. This deserves further attention because I don’t think that all of those who called deterrence into question on account of Russian aggression got it wrong, per se. The concerns ranged from suggesting that deterrence had failed in that it broke down and no longer worked to suggesting that analysts had gotten their calculations wrong.[51] This early panic also largely focused on the failure of the West/the US to deter Russia from invading Ukraine—not to deter Russia from using nuclear weapons. The former is arguably lower on the escalation ladder than the latter, but still stunningly significant: Russia’s actions were brazen, and in violation of Westphalian norms of sovereignty that have endured for generations.
Bell does speak to some of this deterrence-backlash: he quotes Beatrice Fihn, who tweeted “we have to stop being so stupid by continuing to say nuclear deterrence works.” But he quotes Fihn in focusing on reactions that, he writes, support the idea that “the United States should ignore the deterrent effects of Russian nuclear weapons and act confidently and free of fear of Russian escalation in order to enable decisive victory,” which is not quite what Fihn is getting at. The problem with Fihn’s approach is not that it supports the idea that deterrence doesn’t work, so do what you like. The problem is that deterrence isn’t binary as Fihn suggests: while the use of a nuclear weapon is binary, there can be a “deterring effect” in place that, for example, says nothing of the deterrence of the initial aggression that started a conflict on one end or the deterrence of the use of nuclear weapons on the other. In this light deterrence doesn’t 100 percent fail or succeed (and I think Bell would agree).
Other authors cited in the category of critics, charges Bell, essentially reveal their bias that the West is “choosing” to be deterred by “illusory threats.” The question of whether the quotations chosen indeed support this line of thinking aside, the category of critics that Bell describes is different from what I would call “those who called deterrence into question when the war broke out,” of which Fihn is a part. And she is not alone. The deterrence-panic that followed the outbreak of the war cast doubt on deterrence’s ability to deter Russia from invading or that cast doubt on our understanding of deterrence in a new, post-post Cold War security environment. Writing for CSIS, for example, Benjamin Jensen wrote that Russia’s invasion of Ukraine was both a “triumph and failure” for deterrence due to the fact that “Kyiv didn’t sufficiently deny benefits, impose costs, and/or encourage adversary restraint sufficient to stop Russia from invading,” as well as a “extended, general deterrent failure for NATO and EU states who sought ways and means to dissuade Russia from using force to settle territorial disputes.” It was a success, he argues, insomuch as it confined the war to Ukraine and limited the use of weapons of mass destruction (the constraining effect to which Bell alludes).[52] Additionally, writing in the blog pages of Foreign Policy, Liam Collins and Frank Sobchak charge that it was US deterrence that failed in Ukraine: “until Feb. 24, 2022, the United States made little effort to deter Russia, despite ample evidence that it intended to invade,”[53] and describe decades of foreign policy neglect on the part of multiple US administrations. They argue that more should have been done—including sending more “sophisticated” weapons to Ukraine in the run up—and sooner.
Elsewhere, my co-author Alexander H. Montgomery and I critique US policy as “escalation averse,” or something akin to the “deterring ourselves” dynamic/phenomenon Bell points out in his essay—but not on account of “illusory threats.”[54] The US response to Russian saber rattling was one of indignation and outrage.[55] Such a response perhaps reveals the foreign policy conviction and (mirror imaging bias) that because the US knew the possibility of its own use of nuclear weapons to be low, the possibility of Russian use—up until now—would have been similarly low. This is likely because the US has not used nuclear weapons since 1945, and because of a series of movements/shifts away from the acceptable use of nuclear weapons since that time.[56] The problem is that ideal, platonic deterrence, which is an abstraction and collection of ideas, exists when both sides share the same concepts and rules—which was not the case at the outset of the Ukraine war. Signaling has helped recalibrate and universalize the deterrence rules of the road since then. Such threats are exactly how a state signals its willingness to use nuclear weapons.[57] This speaks to the idea that, while deterrence has both enabled and constrained certain behaviors in Ukraine, what is left to be analyzed are aspects unique to the current war—namely, Russia’s “saber rattling” and the United States’ indignant response to it.
The war, of course, is not over yet, and we are still waiting for the end game. This means that there is still potentially much to learn. Moreover, were a nuclear weapon to be employed during this conflict, our nuclear knowledge would surely be forced to evolve. As such, Bell is right to qualify his statement about the war not changing our assessment about the role that nuclear weapons play in international politics with the words “so far.”
Furthermore, US critiques of Russian nuclear threats—casting them as “reckless” for example—belies a risk-averse approach. Behavior under the nuclear shadow is play in a sandbox of risk. Accepting the presence of risk means behaving in a way that reflects that potential nuclear use is possible by both sides. By contrast, a risk-averse approach muddies the waters of deterrence concepts, accepting the idea of countries holding one another at risk with their nuclear arsenals, but indicating a preference to avoid risk in articulating a reluctance for their use. All of which is to say that it is too soon to issue the “all clear”: without coherent and shared concepts on what deterrence means and how it works today, there is fertile ground for misperception, and misperceptions cause wars.[58] The task at hand now is a diplomatic one: once again doing the hard work with adversaries—existing or potential—to ensure actors’ understandings of deterrence are shared ones.
“To Be or Not To Be? This Is… the Strategy”
by Polina Sinovets, Odesa Center for Nonproliferation
In the early morning of 24 February 2022, Russia’s brutal attack on Ukraine was accompanied by a televised speech of President Vladimir Putin: “Whoever tries to hinder us or threaten our country or our people should know that Russia’s response will be immediate and will lead you to consequences that you have never faced in your history.”[59] The explicit reference to the possibility of nuclear use has defined Moscow’s war against Ukraine. Since then, the nuclear trump card appeared in Russian official and media rhetoric on an almost monthly basis, thus updating the relevance of nuclear weapons for the twenty-first century. In fact Russia’s war against Ukraine goes on under its “nuclear shadow” while experts keep arguing over whether it brings anything new about our knowledge on nuclear weapons.[60]
In his essay Marc Bell gives a very logical version of the classic Russian proverb that everything new is the well-forgotten old, and that this war is also based on the basic plain-vanilla deterrence, having three dimensions.
First, nuclear weapons keep deterring Moscow and Washington from the direct war with each other when the US “is deterred from intervening directly in the conflict and from supplying Ukraine with some types of military capabilities” while Russia is deterred from escalating the war to the NATO members, therefore not attacking the Western arms shipments in NATO countries that are en route to Ukraine.
Second, nuclear weapons enable both nuclear superpowers to some boldness during the war. In particular, they “played certain role in enabling Putin’s decision to invade Ukraine.” The so-called “aggressive sanctuarisation” or “offensive deterrence” that occurs when a state uses its nuclear arsenal as an umbrella to perform its conventional aggression against non-nuclear state has become quite famous long ago, so it supposedly tells us nothing new about the role of nuclear weapons.[61] Moreover Bell explains the visit of President Joe Biden to Kyiv with the same emboldening function of nuclear weapons, which is of course true, but does not give us the comprehensive picture of how nuclear deterrence has evolved during the war.
Third, the risks of escalation remain the driving engine of nuclear deterrence gravity in this war. In Bell’s opinion, both of rivals are using the Schelling method of threat which leaves something to chance, in which strategic stability becomes so fragile that any small event can work as a detonator causing nuclear escalation.[62] And although the deployment of Russian nuclear weapons in Belarus or the enlargement of NATO to Finland cannot be considered direct escalatory steps, both raise the potential chances for nuclear stalemate since they can also create “additional avenues by which things could spiral out of control.” That is also very true, as escalation signals have become the catalyzing force of mutual deterrence functioning throughout of the war, as Bell argues.
As we know, the devil is always in details, which is not to undermine Bell’s basic arguments but does add some features to the good old and well known.
On political level, the classic general deterrence is evident but two tendencies from both sides can be observed. One is the gradual exhaustion of the Russian deterrence capabilities. This can be observed in the articles of Russian propagandists who call “to raise the fear of nuclear war at the West,” or to put the “nuclear bullet in the revolver drum.”[63] This probably can be explained by two tendencies. On one hand is the inability of Russia to deter the counteroffensive of the Ukrainian forces who are trying to take back the annexed Ukrainian territories in spite of the Russian nuclear warnings. On the other, one can follow the gradual weakening of the Russian nuclear coercion when in 2023 NATO allies started approving in sending Ukraine the weapons types which seemed unthinkable to in 2022 (such as ATACMS missiles or F-16 jets).
Moreover, at times the state’s threat has historically worked out of its codified sphere of extended deterrence And though Bell calls the US “the patron of Ukraine,” there is no document framing this patron–client relationship, while Russia, for its part, proclaims Russians and Ukrainians the same nation, which shows its vital interests in Ukraine. It is necessary to analyze the events of autumn 2022 after the Putin’s famous speech on the annexation of the Ukrainian territories and the hint to “use all means available” to defend those annexed parts as Russia’s own territory. In October 2022, in response to Putin’s speech, the Biden administration sent strong signals to the Russian leadership that any nuclear attack against Ukraine would be met with an allied US-UK and France conventional strike[64] over the Russian forces involved in nuclear actions.[65] Later in autumn, Putin and the Russian foreign ministry denied any intentions to attack Ukraine with nuclear weapons.[66]
Second, while nuclear weapons enabled Russia to invade Ukraine without fear of foreign interference, this “offensive deterrence” function seems to be obvious since the invention of nuclear weapons. At the same time there is a reason to believe that if Ukraine manages to retake its territories in the war with Russia it will be able to diminish the enabling function of nuclear weapons, thereby upsetting the popular opinion that “nuclear actors are more likely to prevail when facing non-nuclear states.”[67]
Third, while the risk of escalation remains a powerful tool for managing deterrence, it has its own very important side effects. One is that threatening escalation and not supporting it with credible arguments or real nuclear posturing deprives deterrence of its credibility, which in the end diminishes its effectiveness proportionally to the growing amount of the hollow threats. This is what occurred with Russia, which published its nuclear threats every month and at the end faced the growing opinion that its deterrence is not working or that its red lines do not exist per se.
The other effect perfectly fits Bell’s classification. In particular, it may be regarded as the extension of “the threat which leaves something to chance,” destroying the arms control system step by step. In February 2023 Putin suspended the New START treaty as a reaction to the “hostile behavior” of the United States,[68] which meant the support of the US for Ukraine. Putin’s October 2023 Valdai Speech offered a direct message on Russia’s readiness to kill the Comprehensive Test Ban Treaty (CTBT) and to start nuclear testing.[69] Of course, this is “creating additional avenues by which things could spiral out of control,” in that arms control treaties are used as hostages whose collapse can make the situation less predictable and more prone for the playing up of nuclear risks.
In sum, nuclear deterrence shows some “old new” features during the war on Ukraine, while it will hopefully prove the Cold War nuclear deterrence reliability without making a new revolution in military affairs. Otherwise, the use of nuclear weapons to achieve political goals may open a new era in what we know about deterrence.
Response by Mark S. Bell, University of Minnesota
I thank Henrik Stålhane Hiim, Amy J. Nelson, and Polina Sinovets for their thoughtful engagement with my essay. I am delighted that they all find much to agree with. In turn, I agree with many of their comments. In my essay, I emphasized that much of what we are seeing in terms of how nuclear weapons are influencing the war in Ukraine should be familiar to scholars of nuclear issues. Nuclear weapons are deterring both Russia and the United States within the conflict (up to a point) and simultaneously enabling both sides to take certain actions within the conflict (up to a point). These political effects emerge from the genuine risk of nuclear escalation that exists in the conflict.
Hiim largely endorses my argument, applying it to ongoing concerns regarding Chinese intentions with respect to Taiwan. He argues that China is unlikely to be learning fundamentally new lessons about the viability of nuclear-enabled conventional aggression from the war in Ukraine. While concerns about nuclear-enabled aggression are reasonable, our assessment of those concerns should not have changed substantially because of the war in Ukraine. Hiim’s expertise on Chinese nuclear thinking is far greater than mine, but his conclusions seem correct to me. Hiim is, I think, also correct to point to the ways in which US resolve might be different in a potential Taiwan contingency that potentially changes some of the dynamics involved: increasing the ease of deterring Chinese adventurism while also increasing the risks of escalation should deterrence fail.
While also largely agreeing with my argument, Sinovets offers some interesting and thoughtful qualifications to it. She argues that the old lesson regarding the enabling effects of nuclear weapons may ultimately be diminished “if Ukraine manages to retake its territories in the war.” I am not so sure. First, the enabling effects of nuclear weapons have always been finite—as I argued, nuclear weapons enable up to a point. Indeed, nuclear weapons can enable states to make dumb choices that ultimately fail to achieve their goals. If that failure occurs, it does not mean that one should conclude that the enabling effect of nuclear weapons were not real or meaningful. And, of course, nuclear-enabled aggression has failed before: witness Pakistan’s inability to hold on to the territory it initially seized in the 1999 Kargil War.
Sinovets also argues Russia has overplayed its nuclear card, because “threatening escalation and not supporting it with credible arguments or real nuclear posturing deprives deterrence its credibility.” Russia has “published its nuclear threats every month and at the end faced the growing opinion that its deterrence is not working or that its red lines do not exist.” I think this would potentially be a dangerous lesson to draw: as I argue in my essay, Russian deterrent threats are working by constraining the United States from doing all sorts of things it might otherwise be tempted to do in the conflict.
I also agree with most of Nelson’s thoughtful commentary. I would highlight two possible areas of disagreement. First, while Nelson argues that “Russia’s ‘saber rattling’ and the United States’ indignant response to it” are “unique to the current war” (emphasis in original), I tend to think that belligerent nuclear saber rattling has been a regular feature of the nuclear age. One does not have to go too far back in time, after all, to recall a US president threatening “fire, fury, and frankly power the likes of which this world has never seen before” against another nuclear-armed state (and a similarly belligerent response from the target of that threat).[70] The broader issue is that the Russian invasion of Ukraine does not seem to me to mark a discontinuity in the way in which nuclear weapons are used or threatened by states seeking to achieve their goals in international politics.
Second, I am not sure I agree that the US approach to Ukraine has been “risk-averse” or that the United States is “indicating a preference to avoid risk in articulating a reluctance for their use.” The United States certainly could be taking on more risk in Ukraine—it could be sending more potent military capabilities; it could have committed US ground forces to fight (or not ruled out doing so); and so on. But the United States could also have taken on a lot less risk if it had wanted to. The United States has, after all, sent a remarkable quantity of military resources to help defend a country it has no treaty obligations to defend. It brought Finland into NATO and in so doing doubled the length of the direct border the alliance shares with Russia. And it sent the US president to walk around outdoors in the capital city of a country under direct attack. In my view, the United States is taking a similar approach to the one it has taken in other crises and conflicts with nuclear-armed states—whether in the Berlin crises, the Cuban Missile Crisis, the various proxy wars during the Cold War, and so on—the United States is willing to take on some risk of escalation as part of an effort to achieve its political goals, but it seeks to calibrate that risk in accordance with the extent of its perceived interests in the conflict. US strategy in Ukraine seems consistent with this longstanding approach, and thus indicates more continuity than change in the way in which nuclear weapons both induce caution but also enable action in US foreign policy (and international politics more broadly).
Once again, I thank Henrik Stålhane Hiim, Amy J. Nelson, and Polina Sinovets for taking the time to engage constructively with my work. I also thank Jennifer Erickson and Diane Labrosse for shepherding this roundtable through the publication process, and Målfrid Braut-Hegghammer and the Alva Myrdal Centre for Nuclear Disarmament at Uppsala University for the invitation to participate in this roundtable and to think about these crucially important issues.
[1] I thank Målfrid Braut-Hegghammer and the Alva Myrdal Centre for Nuclear Disarmament at Uppsala University for the invitation to write this essay, and Kelso Anderson for excellent research assistance and comments.
[2] Nina Tannenwald, “The Bomb in the Background: What the War in Ukraine Has Revealed About Nuclear Weapons,” Foreign Affairs, 24 February 2023, https://www.foreignaffairs.com/ukraine/bomb-background-nuclear-weapons. For a sampling of analyses of the role of nuclear weapons in the war in Ukraine, see, e.g., Caitlin Talmadge, “The Ukraine crisis is now a nuclear crisis,” Washington Post, 27 February 2022, https://www.washingtonpost.com/politics/2022/02/27/ukraine-crisis-is-now-nuclear-crisis/; Olga Oliker, “Putin’s Nuclear Bluff,” Foreign Affairs, 11 March 2022, https://www.foreignaffairs.com/articles/ukraine/2022-03-11/putins-nuclear-bluff; Alexander K. Bollfrass and Stephen Herzog, “The War in Ukraine and Global Nuclear Order,” Survival 64.4 (2022): 7-32; Graham Allison, “Putin’s Doomsday Threat,” Foreign Affairs, 5 April 2022, https://www.foreignaffairs.com/articles/ukraine/2022-04-05/putins-doomsday-threat; Barry R. Posen, “Can Russia and the West Survive a Nuclear Crisis in Ukraine?,” The National Interest, 13 May 2022, https://nationalinterest.org/feature/can-russia-and-west-survive-nuclear-crisis-ukraine-202351; Jeffrey Lewis and Aaron Stein, “Who Is Deterring Whom? The Place of Nuclear Weapons in Modern War,” War on the Rocks, 16 June 2022, https://warontherocks.com/2022/06/who-is-deterring-whom-the-place-of-nuclear-weapons-in-modern-war/; Tatiana Stanovaya, “Putin’s Apocalyptic End Game in Ukraine,” Foreign Affairs, 6 October 2022, https://www.foreignaffairs.com/russian-federation/putin-apocalyptic-end-game-ukraine; Jeremy Shapiro, “We Are on a Path to Nuclear War,” War on the Rocks, 12 October 2022. https://warontherocks.com/2022/10/the-end-of-the-world-is-nigh/; Masha Gessen, “Why Vladimir Putin Would Use Nuclear Weapons in Ukraine,” The New Yorker, 1 November 2022, https://www.newyorker.com/news/our-columnists/why-vladimir-putin-would-use-nuclear-weapons-in-ukraine; Eric Schlosser, “The Greatest Nuclear Threat We Face Is a Russian Victory,” The Atlantic, 18 January 2023, https://www.theatlantic.com/ideas/archive/2023/01/russias-invasion-ukraine-war-nuclear-weapon-nato/672727/; Kristin Ven Bruusgaard, “How Russia Decides to Go Nuclear,” Foreign Affairs, 6 February 2023, https://www.foreignaffairs.com/ukraine/how-russia-decides-go-nuclear; Keir Giles, “Russian Nuclear Intimidation,” Chatham House Research Paper, 29 March 2023, https://www.chathamhouse.org/2023/03/russian-nuclear-intimidation.
[3] This logic is straightforward and widely understood. See, for example, Kenneth Waltz, “The Spread of Nuclear Weapons: More May Be Better,” Adelphi Papers 171 (1981); John J. Mearsheimer, “Nuclear Weapons and Deterrence in Europe,” International Security 9.3 (1984-1985), 21; John Lewis Gaddis, “The Long Peace: Elements of Stability in the Postwar International System,” International Security 10.4 (1986): 121-123; Stephen Van Evera, Causes of War: Power and the Roots of Conflict (Ithaca: Cornell University Press, 1999), chapter 8.
[4] Tannenwald, “The Bomb in the Background.”
[5] Alex Wellerstein, “The Nuclear Dilemma: Deterrence Works, Upto A Point,” Engelsberg Ideas, 7 June 2022, https://engelsbergideas.com/essays/the-nuclear-dilemma-deterrence-works-up-to-a-point/.
[6] Timothy Snyder, “Nuclear War! Why it Isn’t Happening,” Substack post, 8 February 2023, https://snyder.substack.com/p/nuclear-war.
[7] Anne Applebaum, “The War Won’t End Until Putin Loses,” The Atlantic, 23 May 2022, https://www.theatlantic.com/ideas/archive/2022/05/why-ukraine-must-defeat-putin-russia/629940/.
[8] Beatrice Fihn, Twitter.com, 26 March 2023, https://twitter.com/BeaFihn/status/1640022004580470787?s=20.
[9] Giles, “Russian Nuclear Intimidation.”
[10] On some of the ambiguities in how Russia might make nuclear decisions, see Ven Bruusgaard, “How Russia Decides to Go Nuclear.”
[11] For example, S. Paul Kapur, Dangerous Deterrent: Nuclear Weapons Proliferation and Conflict in South Asia (Stanford: Stanford University Press, 2009); Mark S. Bell, “Beyond Emboldenment: How Nuclear Weapons can Change Foreign Policy,” International Security 40.1 (2015): 87-119; Michael D. Cohen, “Fear and Loathing: When Nuclear Proliferation Emboldens,” Journal of Global Security Studies 3.1 (2018): 56-71; Mark S. Bell, Nuclear Reactions: How Nuclear-Armed States Behave (Ithaca: Cornell University Press, 2021).
[12] Bell, Nuclear Reactions.
[13] On Pakistan, see Kapur, Dangerous Deterrent. On South Africa, see Bell, Nuclear Reactions, ch. 3. On Iraq, see Hal Brands and David Palkki, “Saddam, Israel, and the Bomb: Nuclear Alarmism Justified?,” International Security 36.1 (2011): 133-166.
[14] Giles, “Russian Nuclear Intimidation.”
[15] E.g., Chris Buckley, “China Draws Lessons from Russia’s Losses in Ukraine, and its Gains,” New York Times, 1 April 2023, https://www.nytimes.com/2023/04/01/world/asia/china-russia-ukraine-war.html.
[16] As of February 2023, the United States had committed about $30bn in security assistance since Russia’s invasion. US Department of Defense, “Fact Sheet on U.S. Security Assistance to Ukraine, 3 February 2023, https://media.defense.gov/2023/Feb/03/2003155499/-1/-1/0/20230119-UKRAINE-FACT-SHEET-FEB-3.PDF.
[17] Kevin Liptak, “Biden makes surprise visit to Ukraine for first time since full-scale war began,” CNN, 20 February 2023, https://www.cnn.com/2023/02/20/politics/biden-ukraine-zelensky-visit-one-year-war-anniversary-intl-hnk/index.html
[18] CBS News, “U.S. alerted Russia to Biden’s Ukraine visit for “deconfliction purposes,” White House says,” 20 February 2023, https://www.cbsnews.com/news/biden-ukraine-kyiv-visit-russia-deconfliction-white-house/.
[19] Austin Carson, “Facing off and Saving Face: Covert Intervention and Escalation Management in the Korean War,” International Organization 70.1 (2016): 103-131; Noel Anderson, “Competitive Intervention, Protracted Conflict, and the Global Prevalence of Civil War,” International Studies Quarterly 63.3 (2019): 692-706.
[20] Dan Altman, “Advancing without Attacking: The Strategic Game Around the Use of Force,” Security Studies 27.1 (2018): 58-88. For an application of this framework to Ukraine which argues that the west could do more without provoking an undue risk of war, see Dan Altman, “The West Worries Too Much About Escalation in Ukraine,” Foreign Affairs, 12 July 2022, https://www.foreignaffairs.com/articles/ukraine/2022-07-12/west-worries-too-much-about-escalation-ukraine.
[21] Lewis and Stein, “Who is Deterring Whom?”
[22] Thomas C. Schelling, Arms and Influence (Cambridge: Harvard University Press, 1966)
[23] On variation among nuclear crises, see Mark S. Bell and Julia Macdonald, “How to Think About Nuclear Crises,” Texas National Security Review 2.2 (2019): 40-64. For various work on the risks of nuclear accidents or risks within nuclear crises, see, for example, Scott D. Sagan, The Limits of Safety: Organizations, Accidents, and Nuclear Weapons (Princeton: Princeton University Press, 1993); Eric Schlosser, Command and Control: Nuclear Weapons, the Damascus Accident, and the Illusion of Safety (New York: Penguin, 2013); Benoît Pelopidas, “The Unbearable Lightness of Luck: Three Sources of Overconfidence in the Manageability of Nuclear Crises,” European Journal of International Security 2.2 (2017): 240-262; Benoît Pelopidas and Alex Wellerstein, “The Reason We Haven’t Had Nuclear Disasters isn’t Careful Planning. It’s Luck,” Washington Post, 10 August 2020, https://www.washingtonpost.com/outlook/2020/08/10/reason-we-havent-had-nuclear-disasters-isnt-careful-planning-its-luck/; Reid B.C. Pauly and Rose McDermott, “The Psychology of Nuclear Brinkmanship,” International Security 47.3 (2023): 9-51; Sergey Radchenko and Vladislav Zubok, “Blundering on the Brink: The Secret History and Unlearned Lessons of the Cuban Missile Crisis,” Foreign Affairs, 3 April 2023, https://www.foreignaffairs.com/cuba/missile-crisis-secret-history-soviet-union-russia-ukraine-lessons.
[24] Amy J. Nelson and Alexander H. Montgomery, “How Not to Estimate the Risk of Nuclear War,” Brookings Institute, 19 October, 2022, https://www.brookings.edu/blog/order-from-chaos/2022/10/19/how-not-to-estimate-the-likelihood-of-nuclear-war/.
[25] Schelling, Arms and Influence, 99.
[26] BBC News, “Putin: Russia to Station Nuclear Weapons in Belarus,” 26 March 2023), https://www.bbc.com/news/world-europe-65077687.
[27] Fred Kaplan, “What Putin’s Latest Nuke Announcement Really Means,” Slate, 27 March 2023, https://slate.com/news-and-politics/2023/03/putin-russia-nuclear-weapons-belarus.html.
[28] CNN, “Finland joins NATO, Doubling Military Alliance’s Border with Russia in a Blow for Putin,” 4 April 2023, https://www.cnn.com/2023/04/04/europe/finland-joins-nato-intl/index.html.
[29] Schelling, Arms and Influence, 104.
[30] I discuss this issue in Mark S. Bell, “The Nuclear Taboo and the Inevitability of Uncertainty,” Security Studies 32.1 (2023): 166-172.
[31] See, for example, David Sacks, “What Is China Learning from Russia’s War in Ukraine?” Foreign Affairs, May 16, 2022, https://www.foreignaffairs.com/articles/china/2022-05-16/what-china-learning-russias-war-ukraine
[32] Thomas J. Christensen, “The Meaning of the Nuclear Evolution: China’s Strategic Modernization and US-China Security Relations,” Journal of Strategic Studies 35.4 (2012): 447-487; see also Michael S. Chase, “China’s Transition to a More Credible Nuclear Deterrent: Implications and Challenges for the United States,” Asia Policy, 16 (2013), 69-102.
[33] See, for example, Robert Jervis, The Meaning of the Nuclear Revolution: Statecraft and the Prospect for Armageddon, (Ithaca: Cornell University Press, 1989).
[34] Glenn H. Snyder, “The Balance of Power and the Balance of Terror,” in Paul Seabury, ed., Balance of Power (San Francisco, CA: Chandler Publishing Company 1965), 184–201.
[35]Avery Goldstein, “First Things First: The Pressing Danger of Crisis Instability in US-China Relations,” International Security 37.4 (2013): 66; see also Christensen, “The Meaning of the Nuclear Evolution.”
[36] Even if this projection proves correct, China will not be even near parity with the United States, which has more than 3700 nuclear warheads deployed or in storage. See Office of the Secretary of Defense, Military and Security Developments Involving the People’s Republic of China 2023 (Washington, DC: Department of Defense, 2022), 104; Hans M. Kristensen and Matt Korda, “United States nuclear weapons, 2023,” Bulletin of the Atomic Scientists, 79.1 (2023): 28-52.
[37] Abraham M. Denmark and Caitlin Talmadge, “Why China Wants More and Better Nukes,” Foreign Affairs, November 19, 2021, https://www.foreignaffairs.com/articles/china/2021-11-19/why-china-wants-more-and-better-nukes.
[38] David C. Logan and Phillip C. Saunders, Discerning the Drivers of China’s Nuclear Force Development: Models, Indicators, and Data, (Washington, DC: National Defense University Press, 2023).
[39] See Henrik Stålhane Hiim, M. Taylor Fravel, and Magnus Langset Trøan, “The Dynamics of an Entangled Security Dilemma: China’s Changing Nuclear Posture.” International Security 47.4 (2023): 147-187. In our examination of Chinese nuclear debates, we found no direct discussions of the need for a nuclear “shield.” For another somewhat skeptical take on the “shield” hypothesis, see Fiona S. Cunningham, “The Unknowns about China’s Nuclear Modernization Program,” Arms Control Today 53.5 (2023): 6-14.
[40] PLA Daily, “Eluosi tichu jundui gaige xin jihua” [Russia proposes new plan for military reform], January 12, 2023, http://military.people.com.cn/n1/2023/0112/c1011-32605114.html. See also Lyle Goldstein and Nathan Waechter, “China Studies Nuclear Risk in the Context of the Ukraine War,” The Diplomat, July 21, 2023, https://thediplomat.com/2023/07/china-studies-nuclear-risk-in-the-context-of-the-ukraine-war/
[41] Jervis, The Meaning of the Nuclear Revolution.
[42] BBC News, “Russia Ukraine: Sending US troops not on the table”, December 8, 2021, https://www.bbc.com/news/world-europe-59582013
[43] See, for example, the exchange between Bonnie S. Glaser; Michael J. Mazarr; Michael J. Glennon; Richard Haass and David Sacks, “Dire Straits: Should American Support for Taiwan be ambiguous”, Foreign Affairs, September 24, 2020, https://www.foreignaffairs.com/articles/united-states/2020-09-24/dire-straits
[44] Kevin Liptak, “Biden’s past promises for US to defend Taiwan under microscope in meeting with China’s Xi”, CNN, November 14, 2022, https://edition.cnn.com/2022/11/13/politics/joe-biden-taiwan/
[45] Thomas J. Christensen, M. Taylor Fravel, Bonnie S. Glaser, Andrew J. Nathan and Jessica Chen Weiss, “How to Avoid a War Over Taiwan,” Foreign Affairs, October 13, 2022, https://www.foreignaffairs.com/china/how-avoid-war-over-taiwan
[46] Mark F. Cancian, Matthew Cancian, and Eric Heginbotham, The First Battle of the Next War: Wargaming a Chinese Invasion of Taiwan, (Washington, DC: CSIS, 2023).
[47] Hiim, Fravel and Trøan, “The Dynamics of an Entangled Security Dilemma.”
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